This is a Phase II, multicenter study of low-dose interleukin-2 (IL-2) by sub-cutaneous injection in combination with antiretroviral therapy versus anti-retroviral therapy alone in patients with HIV-1 infection and at least three months stable antiretroviral therapy. IL-2 effect on CD4 lymphocyte count will be studied, and the two regimens will be compared with regard to clinical safety and tolerability, and safety respecting viral load using HIV RNA by bDNA analysis.